The MOCVD method employs organometallic compounds which decompose at a temperature below 1100.degree. C. with the deposition of the metal. Typical equipment which at present is used for MOCVD consists of a "bubbler" with a supply for the organometallic components, a reaction chamber which contains the substrate to be coated and a source for a carrier gas which should be inert with respect to the organometallic component. The "bubbler" is maintained at a constant, relatively low temperature which is preferably above the melting point of the organometallic compound, but far below the decomposition temperature. The reaction or decomposition chamber preferably has a much higher temperature, which is below 1100.degree. C., at which the organometallic compound decomposes completely and the metal is deposited. By means of the carrier gas, the organometallic compound is converted to the vapor state and, together with the carrier gas, transferred into the decomposition chamber. The mass flow of the vapor is easily controlled, and this also permits controlled growth of the thin layer.
The other methods of gas phase deposition essentially differ therefrom only by the manner in which the energy required for the decomposition is supplied.
Hitherto the standard MOCVD processes for generating layers containing elements of group V have mainly employed, for example, AsH.sub.3 or PH.sub.3, which do however have major drawbacks such as toxicity and spontaneous inflammability. Their preparation, transport, storage, and the use of these compounds therefore requires elaborate safety precautions.